Forgot your Password

If you have forgotten your password, please enter your account email below and we will reset your password and email you the new password.


Login to SciCrunch


Register an Account

Delete Saved Search

Are you sure you want to delete this saved search?


NIF LinkOut Portal


Normal lung development in RAIG1-deficient mice despite unique lung epithelium-specific expression.

Xu J, Tian J, Shapiro SD
American journal of respiratory cell and molecular biology


RAIG1, 2, and 3 and GPCR5d represent a new subfamily of orphan G protein-coupled receptors. RAIG1 is expressed abundantly and specifically in the lung during development and in adult mice. During lung development, RAIG1 expression is initiated at E14.5 and gradually increases, reaching its highest levels at E18. High levels of expression are maintained in adult lungs. Given its abundant lung-specific expression and role in retinoic acid signaling, we hypothesized that RAIG1 plays a role in epithelial cell differentiation during lung development. To determine RAIG1 function and track endogenous RAIG1 spatial expression, a null allele of Raig1 was generated and the lacZ gene was "knocked-in." Although expression was detected in both proximal and distal epithelium during embryogenesis, it became restricted to type I and type II pneumocytes and the most distal bronchiolar cells in postnatal lungs. This is the first gene known to have this unique epithelial cell expression pattern. Despite this high level of expression, targeted inactivation of Raig1 did not cause significant developmental defects. Epithelial cell differentiation was normal and lung structure was intact. Analysis of other family members demonstrated some overlapping embryonic expression of RAIG3 mRNA that could have led to functional redundancy in the single RAIG1 null mutant mouse.

  1. Welcome

    Welcome to NIF. Explore available research resources: data, tools and materials, from across the web

  2. Community Resources

    Search for resources specially selected for NIF community

  3. More Resources

    Search across hundreds of additional biomedical databases

  4. Literature

    Search Pub Med abstracts and full text from PubMed Central

  5. Insert your Query

    Enter your search terms here and hit return. Search results for the selected tab will be returned.

  6. Join the Community

    Click here to login or register and join this community.

  7. Categories

    Narrow your search by selecting a category. For additional help in searching, view our tutorials.

  8. Query Info

    Displays the total number of search results. Provides additional information on search terms, e.g., automated query expansions, and any included categories or facets. Expansions, filters and facets can be removed by clicking on the X. Clicking on the + restores them.

  9. Search Results

    Displays individual records and a brief description. Click on the icons below each record to explore additional display options.